Volt Normals · VN-1

Climatology that admits the trend

The documented, persistent mispricing in weather markets is stale climatology: 10- and 30-year normals lag the warming trend — and the warm tails are fattening faster than the means. Volt Normals fit an exact quantile regression on year per station, per day-of-year, per quantile, and evaluate it at this year. Free to cite with attribution ("Volt Normals (Voltcast)" + link).

Today — trend-adjusted vs stale, °C

Full-year CSV, all stations →
Station Tmax normal (VN-1) Stale climatology Stale bias Q90 today Trend Q50 Trend Q90
EBBR Brussels Airport 22.7 21.0 +1.7 29.5 +1.67°C/dec +1.92°C/dec
EDDL Düsseldorf Flughafen 24.4 22.2 +2.2 30.5 +2.86°C/dec +1.82°C/dec
EDDM München Flughafen 23.3 21.1 +2.2 28.4 +1.11°C/dec +1.00°C/dec
EETN Tallinn Lennart Meri 19.1 18.4 +0.7 26.3 +0.91°C/dec +4.17°C/dec
EFHK Helsinki-Vantaa 19.1 17.8 +1.3 24.5 +0.90°C/dec +2.40°C/dec
EGLC London City Airport 21.7 20.2 +1.5 28.3 +1.82°C/dec +3.33°C/dec
EGLL London Heathrow 21.2 21.3 -0.1 29.7 +0.33°C/dec +3.38°C/dec
EHAM Amsterdam Schiphol 22.2 20.3 +1.9 28.8 +1.82°C/dec +3.82°C/dec
EIDW Dublin Airport 18.2 17.8 +0.4 21.8 +0.90°C/dec +0.88°C/dec
EKBI Billund Lufthavn 21.2 18.9 +2.3 26.1 +2.17°C/dec +3.70°C/dec
EKCH København Kastrup 21.2 19.2 +2.0 24.7 +1.75°C/dec +2.75°C/dec
ENBR Bergen Flesland 18.2 16.1 +2.1 21.9 +2.00°C/dec +2.88°C/dec
ENGM Oslo Gardermoen 18.1 17.2 +0.9 23.4 +0.42°C/dec +2.25°C/dec
ENTC Tromsø Langnes 13.0 12.5 +0.5 19.4 +0.18°C/dec +2.00°C/dec
ENVA Trondheim Værnes 18.1 16.6 +1.5 23.3 +1.29°C/dec +1.58°C/dec
ENZV Stavanger Sola 18.8 17.2 +1.6 23.2 +1.57°C/dec +3.00°C/dec
EPWA Warszawa-Okecie 24.8 21.7 +3.1 31.7 +2.78°C/dec +3.71°C/dec
ESMS Malmö Sturup 21.4 18.8 +2.6 26.5 +2.09°C/dec +4.00°C/dec
ESSA Stockholm-Arlanda 17.8 18.0 -0.2 23.1 -0.50°C/dec +0.55°C/dec
EVRA Rīga Airport 21.4 16.3 +5.1 26.8 +2.18°C/dec +4.20°C/dec
LBSF Sofia Airport 27.8 26.3 +1.5 32.0 -0.77°C/dec 0.00°C/dec
LDZA Zagreb Pleso 26.5 23.8 +2.7 33.4 +0.50°C/dec +2.00°C/dec
LEMD Madrid-Barajas 29.6 30.6 -1.0 33.2 -1.33°C/dec -1.88°C/dec
LFPB Paris-Le Bourget 24.1 23.6 +0.5 30.9 +1.27°C/dec +1.78°C/dec
LFPO Paris-Orly 24.1 23.6 +0.5 32.0 +1.23°C/dec +2.82°C/dec
LGAV Athens Eleftherios Venizelos 30.6 30.1 +0.5 34.0 -0.14°C/dec +0.08°C/dec
LHBP Budapest Liszt Ferenc 27.6 25.1 +2.5 34.5 +1.25°C/dec +2.31°C/dec
LIML Milano Linate 28.0 27.4 +0.6 32.0 0.00°C/dec +1.00°C/dec
LIRF Roma Fiumicino 29.1 27.9 +1.2 32.5 +1.00°C/dec +1.82°C/dec
LJLJ Ljubljana Brnik 26.4 25.2 +1.2 31.3 +1.33°C/dec +1.38°C/dec
LKPR Praha-Ruzyně 22.9 21.5 +1.4 30.5 +1.29°C/dec +2.54°C/dec
LOWW Wien-Schwechat 25.7 23.0 +2.7 32.5 +1.25°C/dec +2.60°C/dec
LPPT Lisboa Humberto Delgado 25.5 27.9 -2.4 30.5 -1.67°C/dec -2.50°C/dec
LROP București Otopeni 30.3 27.3 +3.0 35.8 +1.45°C/dec +3.18°C/dec
LSZH Zürich Kloten 23.6 21.9 +1.7 29.3 +0.75°C/dec +0.67°C/dec
LTAC Ankara Esenboga 30.5 27.7 +2.8 34.3 +2.31°C/dec +1.11°C/dec
LTFM Istanbul Airport 27.1 29.3 -2.2 32.8 -2.78°C/dec +0.33°C/dec
LWSK Skopje Airport 31.2 29.2 +2.0 36.3 +0.83°C/dec +1.54°C/dec
LYBE Beograd Nikola Tesla 29.6 26.6 +3.0 34.2 +2.11°C/dec +0.83°C/dec
LYPG Podgorica Airport 31.2 30.5 +0.7 35.3 +0.80°C/dec +1.00°C/dec
LZIB Bratislava M. R. Štefánik 26.1 24.4 +1.7 32.2 +0.79°C/dec +1.62°C/dec
UUEE Moscow Sheremetyevo 22.8 18.7 +4.1 29.0 +4.17°C/dec +5.00°C/dec

"Stale bias" = VN-1 minus the plain multi-decade mean for today's calendar day — the number a stale-normals model misprices by. An amber Q90 trend above the Q50 trend is the tail fattening faster than the mean.

Methodology — VN-1

  • Window: the last 15 completed years of finalized daily Tmax/Tmin (ISD + METAR), ±7-day day-of-year window (15-day centred, leap-stable).
  • Model: exact linear quantile regression (pinball loss, no regularization) of temperature on year — separately for q10/q50/q90 of Tmax and Tmin, so each quantile carries its own trend.
  • Output: the fit evaluated at the current year, plus trend slopes in °C/decade. Rows carry sample sizes; method changes version (VN-2, …) and are never applied silently.
  • Where it works: our degree-day settle projections use VN-1 beyond the ensemble horizon — the projection inherits the trend instead of a stale mean.

Use it

curl "https://voltcast.com/api/v1/normals"          # today, all stations
curl "https://voltcast.com/api/v1/normals/LFPB"     # full-year curve, Paris-Le Bourget

Keyless and CORS-open. The station-exact forecast distributions, settle projections and degree-day trackers built on top are included in Scale and previewed on the Desk demo.